A tobacco redrying plant condensate water recovery and waste heat utilization system

Abstract

The utility model provides a kind of tobacco redrying factory condensate water recovery and waste heat utilization system, through condensate water recovery unit, waste heat utilization unit, water quality treatment monitoring and recycling unit are connected in series to form closed loop operation system in proper order, three major core modules collaborative work, through the integrated technical system of "closed type recovery+ waste heat utilization+ water quality treatment+ multi-scene reuse" realization condensate water whole-process recovery, waste heat efficient conversion and water quality accurate adaptation.The utility model has the functions of efficient recovery of condensate water, deep purification of impurities, full utilization of waste heat, etc., can effectively solve the problems of waste heat waste and water resource loss caused by direct discharge of high-temperature condensate water in tobacco redrying factory, effectively adapt to the steam characteristics and production needs of tobacco redrying enterprises under the municipal central heating mode, reduce water resource consumption and energy loss in tobacco redrying factory, ensure the stability of production water, and improve the overall production economy.

Description

Technical Field

[0001] This utility model relates to a technology for condensate recovery and waste heat utilization in tobacco re-drying plants, and more specifically, a system for condensate recovery and waste heat utilization in tobacco re-drying plants with direct municipal steam supply. Background Technology

[0002] In the tobacco re-drying process, steam, as the core heat source, is widely used in key steps such as tobacco drying and rehumidification. Its supply stability and energy utilization efficiency directly affect the quality of the re-dried product and the company's production costs. With the integrated development of urban energy supply, more and more tobacco re-drying plants are abandoning the traditional model of building their own boiler rooms and adopting direct municipal steam supply. This model has advantages such as energy saving and emission reduction, simple operation and maintenance, and environmental compliance, but it also places special requirements on the subsequent condensate recovery and waste heat utilization.

[0003] Currently, steam condensate recovery systems in tobacco re-drying plants are mostly designed for self-built boilers, resulting in poor compatibility with direct municipal steam supply. Municipal steam, during long-distance transport, is subject to pressure fluctuations and the introduction of small amounts of impurities. Existing recovery systems lack targeted pretreatment and pressure adaptive mechanisms, leading to pipe cavitation, equipment wear, and other malfunctions during condensate recovery, affecting system stability. Furthermore, current technologies utilize condensate waste heat in a limited way, primarily for preheating and makeup water, failing to integrate with the energy needs of multiple stages in the tobacco re-drying process, such as rehumidification and preheating, resulting in the direct discharge of large amounts of low- and medium-temperature waste heat and energy waste. Additionally, some open-type recovery systems allow condensate to come into contact with air, causing oxygen corrosion in pipes, shortening equipment lifespan, and increasing maintenance costs. Furthermore, municipal steam supply is subject to unified scheduling, requiring re-drying plants to dynamically adjust steam consumption based on production load. However, existing recovery systems have slow response times, making it difficult to match fluctuations in municipal steam supply, further reducing condensate recovery efficiency and the continuity of waste heat utilization. Therefore, designing a highly adaptable, efficient, and stable condensate recovery and waste heat utilization system, tailored to the specific characteristics of direct municipal steam supply, has become an urgent need for tobacco re-drying plants to achieve energy conservation, emission reduction, cost reduction, and efficiency improvement. Utility Model Content

[0004] To address the aforementioned technical issues, this utility model proposes a condensate recovery and waste heat utilization system for tobacco re-drying plants. Through an integrated technical system of "closed-loop recovery + waste heat utilization + water treatment + multi-scenario reuse," it precisely adapts to the characteristics of large fluctuations in steam load and differentiated water demand for multiple processes in tobacco re-drying plants directly supplied with municipal steam, achieving full-process condensate recovery, efficient waste heat conversion, and precise water quality adaptation.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A system for condensate recovery and waste heat utilization in a tobacco re-drying plant, comprising, in sequence: The condensate recovery unit collects high-temperature condensate from various steam-using equipment in the tobacco re-drying plant through a condensate recovery tank, and pumps the collected high-temperature condensate to the waste heat utilization unit through a condensate pressurization pump. The top of the condensate recovery tank is equipped with a spray nozzle. The waste heat utilization unit is equipped with multiple sets of plate heat exchangers. Each set of plate heat exchangers uses high-temperature condensate pumped by a condensate pressurization pump as the heat medium and ambient-temperature fresh air delivered from the fresh air duct of the leaf humidifier as the coolant. The condensate after heat exchange through the plate heat exchangers is output in two directions: one direction flows back to the condensate recovery tank and is sprayed into the condensate recovery tank through the spray nozzle; the other direction is sent to the iron removal unit of the water quality treatment, monitoring and reuse unit. The water quality treatment, monitoring, and reuse unit removes iron impurities from the condensate using the iron removal unit. It also monitors the water quality of the condensate after iron removal online using water quality monitoring elements. The qualified condensate is output in two paths: one path is sent to a condensate tank for heat preservation and storage, supplying water for high-temperature water use scenarios; the other path is sent to a softening tank for supplying water for normal-temperature water use scenarios.

[0006] The structural features of this utility model also lie in: The top inlet of the condensate recovery tank is connected to the condensate recovery main pipe, which receives high-temperature condensate from various steam-using equipment in the tobacco re-drying plant. The steam-using equipment includes the steam heating sections of the re-drying machine, dryer, and leaf humidifier, and each has its own condensate outlet connected to the condensate recovery main pipe via a pipeline. The temperature of the high-temperature condensate is 90-100℃.

[0007] The condensate pressurization pump is provided with two sets in parallel, one for use and one for standby. The inlet is connected to the bottom outlet of the condensate recovery tank through a pipeline, and the outlet is connected to the heat medium inlet of each set of plate heat exchangers through multiple parallel pipelines.

[0008] The condensate recovery tank is also equipped with a pressure sensor, a safety valve, and an emergency relief valve.

[0009] The condensate water temperature after heat exchange with the ambient temperature fresh air through the plate heat exchanger is 40-60℃; the fresh air temperature after heat exchange through the plate heat exchanger is 40-60℃, and it is sent into the leaf humidifier from the air inlet end of the leaf humidifier.

[0010] The top inlet of the iron removal unit is connected to the heat medium outlet of the plate heat exchanger via a pipeline; the iron removal unit outputs condensate after iron removal through an external pipeline at the bottom outlet. The pipeline is equipped with a water quality monitoring element, which is a conductivity sensor. Downstream of the conductivity sensor, the pipeline splits into two branches. The first branch is used to discharge unqualified condensate, and the second branch is used to transport qualified condensate. The second branch is further divided into two paths: one leads to the condensate tank, and the other leads to the softened water tank.

[0011] The condensate tank is an insulated hot water tank, and the tank outlet is connected to the de-heating spray interface of the de-heating device, the water supply port of the steam accumulator, and the hot water interface for rinsing the process equipment via pipelines.

[0012] The softened water tank is equipped with a condensate inlet at the top for injecting condensate water, and a water supply outlet for replenishing water. The tank outlet supplies water to the process water equipment of the tobacco re-drying plant, the air conditioning humidification system and the circulating cooling water supply outlet through external pipelines.

[0013] The tobacco re-drying plant obtains steam through direct municipal steam supply.

[0014] Compared with existing technologies, the beneficial effects of this utility model are reflected in: 1. Adopting a closed-loop integrated design: The condensate recovery, waste heat utilization, water treatment and reuse are all in a closed loop, with no condensate discharge, which can avoid water waste and environmental impact, while reducing heat loss and improving energy utilization. 2. Waste heat utilization is precisely matched with process requirements: Waste heat utilization is directly connected to the fresh air preheating process of the leaf humidifier, converting the waste heat of condensate into the heat energy required by the process, without the need for additional heating equipment, and adapting to the temperature requirements of the leaf humidifier process in tobacco re-drying plants. 3. Modular design of water treatment: Through the joint protection of iron removal unit and water quality monitoring elements, the specific requirements of the recycled water quality in tobacco re-drying production can be addressed to ensure that the recycled water quality meets the re-drying process standards and equipment operation requirements. 4. Comprehensive safety protection mechanism: The condensate recovery tank is equipped with a dual overpressure protection system consisting of a safety valve and an emergency relief valve. At the same time, the spray nozzles effectively eliminate exhaust steam, solving the safety hazards and environmental problems of traditional open recovery systems. 5. Strong adaptability: The parameters of each equipment in the system can be flexibly adjusted according to the steam consumption and process water flow of the tobacco re-drying plant, adapting to the intermittent steam consumption and multi-process parallel production characteristics under the municipal steam direct supply mode. In summary, this utility model has functions such as efficient condensate recovery, deep purification of impurities, and full utilization of waste heat. It can effectively solve the problems of waste heat and water resource loss caused by the direct discharge of high-temperature condensate from tobacco re-drying plants. It is effectively adapted to the steam consumption characteristics and production needs of tobacco re-drying enterprises under the municipal centralized heating model, reduces water resource consumption and energy loss in tobacco re-drying plants, ensures the stability of production water, and improves the overall production economy. Attached Figure Description

[0015] Figure 1 This is a process flow diagram of this utility model.

[0016] In the picture: 11 Condensate recovery main pipe; 12 Condensate recovery tank; 13 Spray nozzle; 14 Pressure sensor; 15 Safety valve; 16 Emergency relief valve; 17 Liquid level monitoring components; 18 Tank drain pipe; 19 Tank outlet pipe; 110 Return pipe; 111 Condensate booster pump; 21 Plate heat exchanger (primary type); 22 Plate heat exchanger (secondary type); 23 Heat medium inlet pipeline; 24 Heat medium outlet pipeline; 25 Bypass between heat medium inlet and outlet; 31 Iron removal unit; 32 Condensate inlet pipe before iron removal; 33 Condensate outlet pipe after iron removal; 34 Conductivity sensor; 35 First branch; 36 Second branch; 37 Compressed air pipe; 38 Backwash pipe; 39 Sewage discharge pipe of iron removal unit. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below in conjunction with the embodiments of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0018] Please refer to Figure 1 The condensate recovery and waste heat utilization system for the tobacco re-drying plant in this embodiment includes, in sequence, the following processes: The condensate recovery unit collects high-temperature condensate from various steam-using equipment in the tobacco re-drying plant through a condensate recovery tank, and pumps the collected high-temperature condensate to the waste heat utilization unit through a condensate pressurization pump. The top of the condensate recovery tank is equipped with a spray nozzle. The waste heat utilization unit is equipped with multiple plate heat exchangers. Each plate heat exchanger uses high-temperature condensate pumped by the condensate pressurization pump as the heat medium and ambient-temperature fresh air delivered from the fresh air duct of the leaf humidifier as the coolant. The condensate after heat exchange through the plate heat exchangers is output in two ways: one way flows back to the condensate recovery tank and is sprayed into the condensate recovery tank through the spray nozzle, and the other way is sent to the iron removal unit of the water quality treatment, monitoring and reuse unit. The water quality treatment, monitoring, and reuse unit removes iron impurities from the condensate using an iron removal unit. The water quality of the condensate after iron removal is monitored online using water quality monitoring elements. The qualified condensate is output in two paths: one path is sent to a condensate tank, where the condensate is stored and insulated for use in high-temperature water scenarios; the other path is sent to a softening tank, where the condensate is used for use in normal-temperature water scenarios.

[0019] The structural features of this utility model also lie in: The top inlet of the condensate recovery tank is connected to the condensate recovery header, which receives high-temperature condensate from various steam-using equipment in the tobacco re-drying plant. The steam-using equipment includes the steam heating sections of the re-drying machine, dryer, and leaf humidifier, and each has its own condensate outlet connected to the condensate recovery header via a pipeline. The temperature of the high-temperature condensate is 90-100℃.

[0020] The condensate booster pump has two sets connected in parallel, with one set in use and the other on standby. The inlet is connected to the bottom outlet of the condensate recovery tank through a pipeline, and the outlet is connected to the heat medium inlet of each set of plate heat exchangers through multiple parallel pipelines.

[0021] The condensate recovery tank is also equipped with a pressure sensor, a safety valve, and an emergency relief valve. A level monitoring device is also installed on the tank wall to collect real-time data on the tank's level.

[0022] The condensate water temperature after heat exchange with ambient temperature fresh air via plate heat exchanger is 40-60℃; the fresh air temperature after heat exchange via plate heat exchanger is 40-60℃, and it is sent into the leaf humidifier from the air inlet.

[0023] The top inlet of the iron removal unit is connected to the heat medium outlet of the plate heat exchanger via a pipeline; the iron removal unit outputs the iron-removed condensate through the bottom outlet via an external pipeline. The pipeline is equipped with a water quality monitoring element, which is a conductivity sensor. Downstream of the conductivity sensor, the pipeline splits into two branches. The first branch is used to discharge unqualified condensate, and the second branch is used to transport qualified condensate. The second branch is further divided into two paths: one leads to the condensate tank, and the other leads to the softened water tank.

[0024] The condensate tank is an insulated hot water tank. The tank outlet is connected to the de-heating spray interface of the de-heating device, the water supply port of the steam accumulator, and the hot water interface for rinsing the process equipment via pipelines.

[0025] The softened water tank is equipped with a condensate inlet at the top for injecting condensate water, and a water inlet for replenishing water (softened water). By regulating the flow rate of condensate water and softened water injected into the tank, the liquid temperature inside the tank is kept below 40°C. The tank outlet supplies water to the process water equipment of the tobacco re-drying plant, the air conditioning humidification system, and the circulating cooling water inlet through external pipelines.

[0026] Both the condensate tank and the softened water tank are equipped with liquid level monitoring devices to monitor the water storage level in the tanks in real time.

[0027] The tobacco re-drying plant obtains steam through direct municipal steam supply.

[0028] The following is a combination Figure 1 A detailed introduction to this system: The condensate recovery unit shows: Condensate recovery main pipe 11, condensate recovery tank 12, spray nozzle 13, pressure sensor 14, safety valve 15, emergency relief valve 16, liquid level monitoring component 17, tank drain pipe 18 and matching valves, tank outlet pipe 19, return pipe 110, two sets of condensate booster pumps 111; The waste heat utilization unit shows: 21. Plate heat exchanger (first-stage), 22. Plate heat exchanger (second-stage), 23. Heat medium inlet pipe, 24. Heat medium outlet pipe, 25. Bypass between heat medium inlet and outlet; The water quality treatment, monitoring, and reuse unit shows: Iron removal unit 31, condensate inlet pipe before iron removal 32, condensate outlet pipe after iron removal 33, conductivity sensor 34, first branch pipe 35, second branch pipe 36, compressed air pipe 37 (for connecting compressed air backflushing), backwash pipe 38 (for connecting backwash water (soft water)), and iron removal unit sewage discharge pipe 39.

[0029] The condensate recovery and waste heat utilization system for the tobacco re-drying plant in this embodiment forms a closed-loop operation system by sequentially connecting a condensate recovery unit, a waste heat utilization unit, and a water quality treatment, monitoring, and reuse unit. The three core modules work together to achieve full-process condensate recovery, efficient waste heat conversion, and precise water quality adaptation. The specific operating logic of each unit is as follows: 1. Condensate recovery unit (as an example, it can be arranged in the combined workshop heating station) This unit is the core component for condensate collection and pressure stabilization. Its main function is to receive high-temperature condensate generated by various steam-using equipment in the tobacco re-drying plant, preventing secondary pollution and heat loss caused by the condensate coming into contact with air, and ensuring stable system pressure. The condensate recovery tank is the core equipment, and its volume can be designed according to the hourly steam condensate production of the tobacco re-drying plant to ensure it can buffer high-temperature condensate under fluctuating loads.

[0030] The condensate recovery tank collects high-temperature condensate generated by steam-using equipment such as re-drying machines, dryers, and leaf-moistening machines through the top inlet and condensate recovery header pipe. The outlet is located at the bottom of the tank and is connected to a condensate pressurization pump through a pipeline to transport the high-temperature condensate in the tank to the subsequent waste heat utilization unit. The condensate pressurization pump can be frequency-controlled to adjust the flow rate of high-temperature condensate according to the liquid level in the tank and the needs of the subsequent unit. To ensure the safe operation of the condensate recovery unit, the top of the condensate recovery tank is equipped with a safety valve and an emergency relief valve (the safety valve's set pressure is ≤0.1MPa). The safety valve automatically releases pressure when the tank pressure exceeds the safe range. The emergency relief valve (emergency discharge port set pressure is ≤0.08MPa) serves as backup protection, quickly responding to overpressure situations. Together with the safety valve, they form a dual overpressure protection system, ensuring safe system operation. Both are connected to an external safety relief channel via pipelines to prevent accidents. Inside the condensate recovery tank, at the top, there is a spray nozzle. The nozzle inlet receives return condensate from the waste heat recovery unit via a pipeline. This return condensate condenses the exhaust steam inside the tank, thus eliminating back pressure. The tank wall is also equipped with level and pressure monitoring components to collect real-time data on the tank's level and pressure. This data provides a basis for frequency conversion adjustment of the condensate booster pump and control of the safety valve, stabilizing the back pressure inside the tank at 0.08MPa.

[0031] II. Waste heat utilization unit (as an example, a plate heat exchanger can be arranged in the air inlet section of the leaf humidifier in the combined workshop). This unit is responsible for the conversion of waste heat from condensate and process adaptation. With a plate heat exchanger as its core, it directly matches the fresh air preheating requirements of the leaf humidification process in the tobacco re-drying plant. It converts the waste heat carried by the high-temperature condensate into the heat energy required for the fresh air of the leaf humidifier, thereby reducing the amount of steam consumed by the hot air heating of the leaf humidifier.

[0032] The heat transfer medium inlet of the plate heat exchanger is connected to the outlet of the condensate pressurization pump through a pipe to receive high-temperature condensate (temperature approximately 95℃); the refrigerant inlet of the plate heat exchanger is connected to the fresh air duct of the leaf humidifier (including primary and secondary humidifiers), and the fresh air duct is equipped with fresh air delivery components and filter components to filter the outside air and deliver it to the plate heat exchanger; the refrigerant outlet of the plate heat exchanger is connected to the air inlet of the leaf humidifier through a pipe, and the temperature of the fresh air after heat exchange is raised to 40-60℃. The plate heat exchanger has two outlets for the heat medium: one connects to the spray nozzle inlet at the top of the condensate recovery tank via a return pipe, returning some of the condensate after heat exchange to the tank to eliminate exhaust steam and back pressure; the other connects to the iron removal unit via a pipe, transporting the remaining condensate to subsequent treatment stages. To ensure flexible system operation, bypass pipes and control valves are installed between the heat medium inlet and outlet of the plate heat exchanger. When the heat exchanger needs maintenance, the bypass pipes can maintain condensate supply, preventing a complete system shutdown. A drain channel can also be installed at the bottom of the plate heat exchanger to periodically remove deposited impurities and ensure heat exchange efficiency.

[0033] III. Water quality treatment, monitoring and reuse unit (as an example, it can be arranged in the existing power station building) This unit optimizes condensate water quality and enables its reuse in different scenarios. Through targeted treatment and precise allocation, it meets the water needs of various processes and equipment in tobacco re-drying plants, avoiding water waste and problems such as equipment contamination and scaling. The unit comprises four main components: condensate iron removal treatment, online water quality monitoring, differentiated storage, and reuse allocation. The condensate iron removal process is centered around an iron removal unit, which is connected to the heat medium outlet of a plate heat exchanger via pipeline. It receives condensate that has been cooled to 40-60℃ after heat exchange. The iron removal unit removes iron impurities from the condensate through the action of filter media, ensuring that the iron content of the treated condensate is ≤0.3mg / L, thus avoiding iron impurities from causing scaling on equipment and contaminating tobacco leaves.

[0034] Water quality monitoring elements are installed on the pipeline connected to the outlet of the iron removal unit to monitor indicators such as the conductivity of the condensate in real time. Water quality monitoring elements for monitoring iron content can also be installed. Based on this embodiment, further modifications can be made to transmit the monitoring data to the control center in real time to determine whether the condensate meets the reuse requirements.

[0035] After passing water quality monitoring, the condensate is transported in two pipelines: one enters a condensate tank, which is an insulated storage device to maintain the temperature of the condensate. Its outlet is connected to the enterprise's hot water demand equipment via pipelines, including the spray interface of the steam desuperheating device, the water inlet of the steam accumulator, and the hot flushing water interface of the process equipment, providing a water source for high-temperature water use scenarios; the other enters a softened water tank, which is connected to a softened water preparation system for replenishing the tank with softened water. By regulating the flow rate of condensate and softened water injected into the tank, the liquid temperature inside the tank is kept below 40°C. The outlet of the water tank is connected to process water equipment, air conditioning humidification system, and circulating cooling water inlet via pipelines, providing a suitable water source for normal temperature water use. Both the condensate tank and the softened water tank are equipped with liquid level monitoring components to monitor the water storage volume in real time, providing a basis for water inlet control and reuse distribution; the softened water tank is also equipped with a pressure balancing component on the top to prevent overpressure or negative pressure caused by water inlet or outlet, ensuring stable operation of the water tank.

[0036] The condensate recovery and waste heat utilization system for the tobacco re-drying plant in this embodiment performs as follows after being put into application: 1. High condensate recovery efficiency: The system adopts a closed recovery structure to avoid leakage and pollution caused by condensate contact with air. The condensate recovery rate reaches more than 95%. Compared with the traditional open recovery system, it significantly improves water resource utilization and reduces the fresh water consumption cost of enterprises. 2. Significantly improved waste heat utilization rate: The waste heat of high-temperature condensate is directly used for preheating the fresh air of the leaf humidifier, reducing the steam consumption for steam heating. The waste heat utilization rate reaches more than 85%, which can effectively reduce the energy consumption of the leaf humidifier process and reduce carbon emissions, meeting the requirements of green production. 3. Strong water quality adaptability: Through the design of "iron removal treatment + online monitoring + quality-separated reuse", the iron content of the reused condensate is ensured to be ≤0.3mg / L and the conductivity is ≤100μS / cm, which meets the water quality requirements of different scenarios such as cooling spray, process flushing, and air conditioning humidification, avoids equipment scaling and tobacco pollution, and improves product quality stability. 4. Safe and stable operation: The safety valve and emergency relief valve form a dual overpressure protection, which can quickly release pressure when the system pressure exceeds the set value (such as 0.8MPa) to avoid safety accidents; the spraying achieves rapid condensation of exhaust steam, eliminates exhaust steam accumulation in the tank, and ensures smooth recovery of condensate; the fully closed recovery system isolates condensate from air contact, reduces the electrochemical corrosion of pipelines and tanks by oxygen, and extends the service life of the equipment.

[0037] Adaptable to municipal steam direct supply mode: In view of the intermittent and large peak fluctuation of steam used in tobacco re-drying plants under municipal steam direct supply, the system can adjust the flow rate through the condensate pressurization pump and buffer the water volume in the condensate tank and softened water tank to ensure the dynamic balance between steam supply and water demand, and solve the problems of poor adaptability and large operation fluctuation of traditional systems.

[0038] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A system for condensate recovery and waste heat utilization in a tobacco re-drying plant, characterized in that: In order, they include: The condensate recovery unit collects high-temperature condensate from various steam-using equipment in the tobacco re-drying plant through a condensate recovery tank, and pumps the collected high-temperature condensate to the waste heat utilization unit through a condensate pressurization pump. The top of the condensate recovery tank is equipped with a spray nozzle. The waste heat utilization unit is equipped with multiple sets of plate heat exchangers. Each set of plate heat exchangers uses high-temperature condensate pumped by a condensate pressurization pump as the heat medium and ambient-temperature fresh air delivered from the fresh air duct of the leaf humidifier as the coolant. The condensate after heat exchange through the plate heat exchangers is output in two directions: one direction flows back to the condensate recovery tank and is sprayed into the condensate recovery tank through the spray nozzle; the other direction is sent to the iron removal unit of the water quality treatment, monitoring and reuse unit. The water quality treatment, monitoring, and reuse unit removes iron impurities from the condensate using the iron removal unit. It also monitors the water quality of the condensate after iron removal online using water quality monitoring elements. The qualified condensate is output in two paths: one path is sent to a condensate tank for heat preservation and storage, supplying water for high-temperature water use scenarios; the other path is sent to a softening tank for supplying water for normal-temperature water use scenarios.

2. The condensate recovery and waste heat utilization system for tobacco re-drying plants according to claim 1, characterized in that: The top inlet of the condensate recovery tank is connected to the condensate recovery main pipe, which receives high-temperature condensate from various steam-using equipment in the tobacco re-drying plant. The steam-using equipment includes the steam heating sections of the re-drying machine, dryer, and leaf humidifier, and each has its own condensate outlet connected to the condensate recovery main pipe via a pipeline. The temperature of the high-temperature condensate is 90-100℃.

3. The condensate recovery and waste heat utilization system for tobacco re-drying plants according to claim 1, characterized in that: The condensate pressurization pump is provided with two sets in parallel, one for use and one for standby. The inlet is connected to the bottom outlet of the condensate recovery tank through a pipeline, and the outlet is connected to the heat medium inlet of each set of plate heat exchangers through multiple parallel pipelines.

4. The condensate recovery and waste heat utilization system for tobacco re-drying plants according to claim 1, characterized in that: The condensate recovery tank is also equipped with a pressure sensor, a safety valve, and an emergency relief valve.

5. The condensate recovery and waste heat utilization system for tobacco re-drying plants according to claim 1, characterized in that: The condensate water temperature after heat exchange with the ambient temperature fresh air through the plate heat exchanger is 40-60℃; the fresh air temperature after heat exchange through the plate heat exchanger is 40-60℃, and it is sent into the leaf humidifier from the air inlet end of the leaf humidifier.

6. The condensate recovery and waste heat utilization system for tobacco re-drying plants according to claim 1, characterized in that: The top inlet of the iron removal unit is connected to the heat medium outlet of the plate heat exchanger via a pipeline; the iron removal unit outputs condensate after iron removal through an external pipeline at the bottom outlet. The pipeline is equipped with a water quality monitoring element, which is a conductivity sensor. Downstream of the conductivity sensor, the pipeline splits into two branches. The first branch is used to discharge unqualified condensate, and the second branch is used to transport qualified condensate. The second branch is further divided into two paths: one leads to the condensate tank, and the other leads to the softened water tank.

7. The condensate recovery and waste heat utilization system for tobacco re-drying plants according to claim 1, characterized in that: The condensate tank is an insulated hot water tank, and the tank outlet is connected to the de-heating spray interface of the de-heating device, the water supply port of the steam accumulator, and the hot water interface for rinsing the process equipment via pipelines.

8. The condensate recovery and waste heat utilization system for tobacco re-drying plants according to claim 1, characterized in that: The softened water tank is equipped with a condensate inlet at the top for injecting condensate water, and a water supply outlet for replenishing water. The tank outlet supplies water to the process water equipment of the tobacco re-drying plant, the air conditioning humidification system and the circulating cooling water supply outlet through external pipelines.

9. The condensate recovery and waste heat utilization system for tobacco re-drying plants according to claim 1, characterized in that: The tobacco re-drying plant obtains steam through direct municipal steam supply.

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